China Plans World's Most Extreme Underwater Tunnel

At 76 miles, the tunnel China may soon start constructing beneath the Bohai Sea to connect the port cities of Dalian and Yantai would be longer than the world’s two longest underwater tunnels combined and cost $42.4 billion to complete.

1 minute read

July 15, 2013, 12:00 PM PDT

By Jonathan Nettler @nettsj


Gwynn Guilford examines the superlatives surrounding the planned Bohai Tunnel. If constructing a subterranean tube of extraordinary length and depth weren't complicated enough, the tunnel will have to traverse two active fault zones.

"Though only 105 miles apart as the crow flies, the drive between Dalian and Yantai takes around seven to eight hours. The Bohai Tunnel would shorten that to an hour," says Guilford.

"Provincial leaders of Shandong and Liaoning hope the tunnel will stimulate economic growth by connecting China’s northern rustbelt region with the upper reaches of the wealthy eastern coast. A member of the Chinese Academy of Engineering projected annual revenue of $3.7 billion, largely from freight, meaning the project would potentially pay for itself in 12 years. And if that’s not rationale enough, there’s bonus of claiming another world record (the government seems to have a fondness for superlative infrastructure)."

Friday, July 12, 2013 in Quartz

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